In order to identify functional ability risk factors for adverse mobility outcomes among older drivers, a collaborative study was initiated in 1998 between the Maryland Motor Vehicle Administration (MVA), NHTSA, and the NIA-funded UAB Roybal Center for Research on Applied Gerontology. In this study, a large sample (N=2000+) of older drivers was evaluated with a brief battery of performance-based measures after completing license renewal at several MVA field offices. In addition, a sub-sample (n=850+) of these participants was followed annually by telephone interview for a three year period to monitor changes in their overall mobility. Through that study, a limited set of functional ability tests were deemed useful by the Maryland MVA for further evaluation and potential implementation in the licensing process. In addition, these same measures were found to be predictive of more general declines in mobility obtained through self-report. The present application proposes to re-examine the original participants on a modified version of the screening battery administered five years later during their next license renewal cycle and to monitor, via telephone survey, the mobility of the entire sample over an additional three year period. The primary advantage for continuing to follow this unique and well-characterized sample is that the impact of already identified risk factors can be examined longitudinally, and the trajectory of mobility function over time can be compared for individuals who initially evidenced cognitive and physical difficulties relative to those who did not. A clearer understanding of how risk factors change over time can serve as a basis for developing interventions to promote mobility for older adults, as well as providing information for the development of assessment, referral, and licensing guidelines for state agencies charged with the task of evaluating driving competence.